The present invention relates to a rigidified, conical structure formed of pleated, creped, folded or finely fluted material and has particular application to a lampshade. Although a lampshade is hereafter described, the invention has application to other conical structures formed of pleated material, e.g. a supporting stand, the base of the lamp, etc.
One basic style of lampshade is frustoconically shaped and formed of a finely pleated or fluted material. For stiffening the lampshade and defining its cone angle, a ring is affixed at the upper narrow end of the lampshade and an additional ring may be affixed toward the lower edge of the lampshade. The lampshade may further include ribs joining those rings.
There are extra costs for material and labor associated with the rings and ribs and their assembly. Also, once the rings have been attached to the lampshade material, the conical shape of the lampshade is precisely fixed. A manufacturer must produce a larger inventory of differently sized and shaped lampshades.